it seems mod cannot create thumbnail for the image that is why ymsm_icon_id is negative (-1)
try to create 'ymsm' directory inside your 'forum/cache' and than play with its access mask starting from 777 than 755 an so on

ViolaF wrote:What for a type have the column ymsm_icon_id, when you look at it with phpmyadmin?
I mean INT_TEXT oder TEXT or?

I cannot find ymsm_icon_id in my database??? I have phpbb_icon_id but that's as close as it gets. I have reinstalled the mod and nothing has changed, I still get the same error. I used automod to install.

I upload a geotagged image and can preview the post but when I submit I get the same error, if I back up and try to resubmit I get the following.

[phpBB Debug] PHP Warning: in file [ROOT]/includes/ymsm/image.php on line 304: imagepng() [function.imagepng]: Unable to open './cache/ymsm/marker/2_692d437302d0b576680e5b49a5bbda77.png' for writing: No such file or directory
[phpBB Debug] PHP Warning: in file [ROOT]/includes/ymsm/image.php on line 304: imagepng() [function.imagepng]: Unable to open './cache/ymsm/thumb/2_692d437302d0b576680e5b49a5bbda77.png' for writing: No such file or directory
Warning: Cannot modify header information - headers already sent by (output started at /home/watcher/public_html/work/includes/functions.php:3872) in /home/watcher/public_html/work/includes/functions.php on line 2726
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